In the field of furniture making, the use of sensor devices to control a function of a piece of furniture in various embodiments is known. Corresponding sensor devices can be connected electrically or electronically with, for example, an actuator such as, for example, a drive unit. The actuator can be provided to move a movable part of the piece of furniture such as, for example, a door, a drawer or a furniture flap. The sensor device can, equally, be provided for an operation of a locking device. A sensor device is here frequently provided for a single furniture section of a piece of furniture which is movable or whose state can be changed in some other respect. Embodiments are, however, also known in which a sensor device is provided for a plurality of often similar furniture sections, wherein the sensor device comprises a monitoring region which can be divided into a plurality of partial regions for monitoring by the sensor device, in order to assign one of the furniture sections to each partial region. An actuating action, for example, reaching into a corresponding partial region can be converted by the sensor device into an actuation signal for an actuator of an associated furniture section, in order to actuate the furniture section. The actuation can, for example, be an opening and closing of a drawer.
The present invention is based on the object of providing a piece of furniture that is designed for a comparatively easy and, in particular, contact-free, actuation in an unobtrusive and space-saving manner.
The present invention starts on the basis of a piece of furniture with a sensor device. The heart of the invention is that the sensor device comprises an electrode arrangement which is arranged on a furniture section of the piece of furniture in such a way that, by using the electrode arrangement, changes in an electric field in a surrounding region, which is located at one side of the piece of furniture, can be detected with or without contacting the electrode arrangement or the piece of furniture, and that the sensor device comprises a detection unit by means which a position of a body in the surrounding region of the piece of furniture can be determined by means of a detected change of the electric field. The electrode arrangement can here comprise one or a plurality of electrodes consisting of an electrically conductive material, a metal, for example.
The electrodes are provided for the detection of a change of an electric field in the surrounding region when a dielectric body is moved into or out of the surroundings of the electrodes. The present invention offers the advantage that as a result a simple and space-saving solution can be implemented, in particular, for contact-free actuation.
The present invention is based on the recognition that the human body—in part due to its high water content—can comparatively easily be electrically polarized in a static electric field. In a free region of space that is filled by an electrostatic field, a bodily part of a person can therefore measurably or detectably change an electrostatic field distribution. A bodily part is therefore suitable as a dielectric, polarizable body whose position in the surrounding region of the piece of furniture can be determined or detected. The electrode arrangement is here preferably geometrically constructed in such a way that a plurality of different positions of the bodily part can be distinguished, and, in particular, determined quantitatively, where appropriate with reference to the electrode arrangement, through a corresponding influence on the electric field distribution. A piece of furniture according to the present invention can thus advantageously be designed for actuation with contact and for contact-free actuation.
For the purpose of a contact-free actuation, an electric field distribution can be provided at the piece of furniture which extends with a field strength beyond an outer surface of the furniture section into a surrounding region located in particular outside the piece of furniture. A field change generated by a body, e.g. by a human bodily part, can thus be detected with the electrode arrangement, without contacting or reaching into the piece of furniture being necessary.
A corresponding change to the electric field can here generate a change to a charge at one or a plurality of electrodes of the electrode arrangement. A change to a charge state at one or a plurality of electrodes can be measurable and detectable with the detection unit, for example, making use of currents. Preferably the detection unit is designed in such a way that changes in the state of the electrodes of the electrode arrangement—for example, changes of their charge—can be evaluated with it, and can be communicated, for example, in the form of signals, in particular digital data, to, for example, a control device or, for example, to an actuator such as, for example, an electric drive.
One electrode of the electrode arrangement is preferably manufactured from an electrically conductive material, which can, for example, be a metal, a semiconductor, a plastic or, if appropriate, also a combination of a plurality of different conductive materials. The material can, for example, have a crystalline structure or also, for example, be an amorphously ordered plastic material.
One electrode of the electrode arrangement can be provided as a probe electrode for detecting the electric field distribution in the surrounding region. In order to determine an electric field distribution and, if relevant, its change, with relative precision, the electrode arrangement preferably comprises a plurality of probe electrodes, in particular, arranged separately from each other.
A preferred embodiment of the present invention consists in that a plurality of the probe electrodes can be connected individually to the detection unit for separate detection. A precision of the position determination can be increased through this.
A plurality of the electrodes, in particular, the probe electrodes, can here be indirectly in contact with one another through the detection unit, where each electrode is connected individually to the detection unit.
An electrode of the electrode arrangement can be adapted to a detection connection of the detection unit in such a way that the electrode can be electrically connected directly to the detection unit. Preferably all the electrodes of the electrode arrangement are designed in this way.
An electrode of the electrode arrangement can be designed as a comparatively thin, in particular, flat element, for example, in the form of a plate, and, in particular, of a foil.
It is furthermore preferred for the electrode arrangement to comprise at least one field electrode which is provided to generate an electric field in the surrounding region at the side of the piece of furniture. An electric field with reference to a reference potential in a surrounding region of the piece of furniture, for example, a ground potential of a room or building, can be created with a field electrode. A plurality of field electrodes can be provided here, which if appropriate can be placed at the same or at different electric potentials. In this way influences from the surroundings which could bring about an unfavorable field distribution can be compensated for. An additional field electrode for connection to a ground potential can, for example, be provided.
Preferably the field electrode can be connected for charging to the detection unit. The field strength can in this way be adjusted, and, for example, controlled or regulated, by the detection unit.
A further preferred embodiment of the present invention consists in that the electrode arrangement comprises a carrier element to which the probe electrodes are attached, separated from one another by electrically insulating material. The carrier element can, for example, be a plate-like, rigid body or, for example, a flexible foil which can, if appropriate, be stretched elastically. The electrodes can be attached to it individually or, for example, attached by coating onto a carrier material. The electrode arrangement can in this way be formed as an assembly or as an individual component which can be comparatively easily mounted. The field electrode is preferably attached, electrically insulated, to the carrier element, in order to avoid an influence of one of the probe electrodes on the field electrode.
A particularly preferred embodiment of the present invention consists in that the electrode arrangement is formed on a circuit board. In this way the electrode arrangement can be manufactured comparatively economically and be thin in form.
The surrounding region, which is filled by the electric field for monitoring by the electrode arrangement, is located at a preferably easily accessible side of the piece of furniture. The electrode arrangement can here be arranged on the body of the piece of furniture. The electrode arrangement can, furthermore, be arranged on a movable furniture section. The electrode arrangement can, also, be arranged on a front panel. The electrode arrangement can here be embedded in a component of the piece of furniture with planar extension, for example, in a front panel, in a door, or in a side wall. The electrode arrangement can also be embedded in a cover plate. The cover plate can, for example, be a top plate, a floor plate, a draw bottom, or a horizontally extendable plate.
The detection unit can comprise a microelectronic circuit arrangement with which a comparatively weak change in the field distribution resulting, for example, from human bodily tissue, can be reliably measured. It is, in particular, preferred that the detection unit is formed as an integrated microelectronic component, whereby the detection unit can comparatively easily and in a space-saving manner be screened from external influences, in particular, electromagnetic influences. In a comparatively simple embodiment, the detection unit can process changes at the electrodes, in particular, at the probe electrodes, in such a way that the change can be transmitted in the form, for example, of amplified and, for example, normalized signals to a further electronic unit. A comparatively advanced embodiment of the detection unit according to the prior art is available, for example, with a programmable microcontroller with integrated signal processing unit, with which a movement of the body detected by the electrode arrangement can be followed and, in addition, evaluated and processed.
Preferably, a sequence of a plurality of positions of the dielectric body can be assigned in the surrounding region of an actuation signal by the detection unit. The detection unit preferably evaluates the positions of the body relative to one another, that is to say not absolutely, wherein a movement of the body can be detected as a gesture with a plurality of different positions. Preferably the detection unit is designed for detection of a plurality of gestures, whereby each gesture can be assigned to one of a plurality of different actuation functions for its initiation and control.
A preferred embodiment of the present invention consists in that the piece of furniture comprises an actuator that is connected to a sensor device for an actuation. The actuator can, for example, be a drive motor for moving a movable furniture section, a door-opener or, for example, a locking device of the piece of furniture. For a self-contained embodiment, the sensor device can be connected directly to an actuator or to a plurality of actuators, wherein the sensor device can preferably be designed for a drive and control of the actuators with, in relevant cases, an integrated processor unit, for example, as a system-on-chip (SoC). An actuator can, moreover, be connected indirectly via a control device, for example, a separate computing unit, to the sensor device, whereby signals and, if relevant, data can be made available to not just one actuator or to an actuation or control function.
If a comparatively large number of different gestures can be detected by means of the electrode arrangement and the detection unit, a single electrode arrangement, and a single detection unit, can be employed for the actuation of a plurality of actuators and, in particular, of a plurality of movable furniture sections.